I was just dreaming in head when I came up with a good thread idea. What are your favorite mythological creatures? Mine are werewolves, elves, dragons, ghosts, serpents, gods, goddesses, and vampires. What are yours?

"How sharper than a serpent's tooth is it to have a thankless child?" -William Shakespeare

There's no doubt for me SC...
Mine is "The Cerber" or Cerberus or Cerbère...

According to the mythology :

The monster guard of the Hell. Son of Typhon and Échidna, it was a dog with fifty or hundred heads, according to the authors. In the art it is represented with three heads, a tail of dragon, and heads of snake on the spine. Even deaths themselves were to alleviate it by presenting the honeycake to him that have been placed in their tomb at the same time as the "obole" for Charon. But Cerbère was especially terrible for the people which tried to force the door of the Hell like Pirithoos and Thésée, which thought to kidnapp Perséphone. Orphée calmed it while playing "lyre" to him, then Énée threw to him the cake prepared by Sibyl. Only Héraclès succeeds in overcoming it. He unchained Cerbère and brought it to Trézène, then he bring it back to the Hell.

according to gamers specifications :

Cerbers don’t usually give a good impression when you see one. The incarnation of a wolf spirit, worshipped as a god for almost one milleni, it has gradually spread to some inhabited places in Ganareth.It is very difficult to determine what it feeds on and what sort of hunting ground it likes. This creature often lives in inaccessible locations, endowed with ancient and powerful magic. It is not rare to see one, sometimes several of them, around immortal or apostle hideouts.No courageous adventurer ever came back alive to tell about how they breed. Renowned scientists in the University of Al-Drifa believe, although it has never been proven, that cerbers breed by schizogenesis. If you cut a cerber’s head in the right way, it can create another cerber. The other theory is that new cerbers can breed using a method similar to propagation by cuttings, although this idea implies unspeakable methods.Nobody has ever been able to fight against a cerber and win. Its three heads act independently and with coordination, using their sharp teeth like daggers. Its size and the strength of its rear legs are additional and important assets.It has often been heard that there is some kind of relationship between cerbers and kârh, Ellianor’s white wolf. However, this idea has never been confirmed or invalidated.

Griffins are very cool, but going towards the Lovecraftian mythologies, I really love Cthulu. He is just such an intense and overwhelming entity. I really like Cerberus too, the idea of a three-headed dog is cool. But, weirdly enough, I don't like Hydras. They seem too unstable, and not able to move around easily enough.